ENGINE CONTROL DEVICE AND ENGINE CONTROL METHOD

Abstract

A motor control device (10) comprises: a memory (14) configured to store a phase lead angle map in which a phase lead angle map value and a load factor of a motor (30) are pre-linked; a phase lead angle setting unit (13) configured to calculate a load factor of the motor (30) at a motor application voltage, which is a voltage to be applied to the motor (30), and to set a phase lead angle calculated based on a phase lead angle map value and the motor application voltage; and a PWM drive control unit (17) configured to control the motor at the set phase lead angle. The phase lead angle map value is obtained from the phase lead angle map using the calculated load factor.

Description

CROSS-REFERENCE TO RELATED REGISTRATIONS

[0001] This application is based on Japanese patent application No. 2023-090344, which was filed on May 31, 2023, the description of which is hereby incorporated by reference. TECHNICAL AREA

[0002] The present disclosure relates to an engine control device and an engine control method. STATE OF THE ART

[0003] The use of vector control allows a brushless motor to be adjusted to the optimal current phase despite changes in rotational speed and load. It is possible to reduce the current while maintaining optimal motor characteristics and to bring the brushless motor into efficient operation.

[0004] For example, patent document 1 describes a vector control device for a permanent magnet synchronous motor. The vector control device controls an output voltage of an electrical power converter that drives the permanent magnet synchronous motor, based on a second d-axis current command value calculated from a first d-axis current command value, a second q-axis current command value calculated from a first q-axis current command value, a frequency command value, and motor constant settings.This vector control device includes a motor constant identification arithmetic unit that identifies the motor constant of the permanent magnet synchronous motor connected to the electrical power converter using the second d-axis current command value, the second q-axis current command value, the detected value of an electrical power converter output current, and the motor constant settings. The vector control device then drives the permanent magnet motor using the motor constant identified by the motor constant identification arithmetic unit for a vector control arithmetic operation. REFERENCES ACCORDING TO THE STATE OF THE TECHNOLOGY PATENT DOCUMENT

[0005] Patent document 1: JP 2007 - 049843 A SUMMARY OF THE INVENTION

[0006] Vector control, however, requires a current sensing unit to detect the current and an arithmetic unit to perform an arithmetic operation such as coordinate transformation. In particular, in cases where the current exhibits large fluctuations, the periodicity of the current control must be reduced. This necessitates the use of a microcomputer with high processing power. Therefore, in cases where cost is a primary concern, the phase advance angle is either fixed or, in some cases, preset depending on the rotational speed. In such cases, for applications where the rotational speed and load fluctuate, the d-axis current can increase excessively, potentially reducing efficiency and speed controllability.

[0007] One objective of the present disclosure is to provide a motor control device and a motor control method that makes it possible to control a d-axis current despite changes in the load and rotational speed of the motor, without the need to detect a current and perform complicated arithmetic processing.

[0008] A motor control device according to a first embodiment of the present disclosure comprises: a storage unit configured to store a phase-adjustment angle map in which a phase-adjustment angle map value and a load factor of a motor are pre-linked; a calculation unit configured to calculate a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor; a setting unit configured to set a phase-adjustment angle calculated on the basis of a phase-adjustment angle map value and the motor application voltage; and a drive control unit configured to control the motor at the set phase-adjustment angle. The phase-adjustment angle map value is obtained from the phase-adjustment angle map using the calculated load factor.

[0009] A motor control method according to a second embodiment of the present disclosure is a motor control method performed by a motor control device having a memory unit configured to store a phase-adjustment angle map in which a phase-adjustment angle map value and a load factor of a motor are pre-linked. The motor control method, by the motor control device, comprises: calculating a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor; setting a phase-adjustment angle, which is calculated based on a phase-adjustment angle map value and the motor application voltage; and controlling the motor at the set phase-adjustment angle. The phase-adjustment angle map value is obtained from the phase-adjustment angle map using the calculated load factor.

[0010] The technology according to the disclosure has advantageous effects in that, despite changes in the load and rotational speed of a motor, the control of a d-axis current is permitted without the need to detect a current and perform complicated arithmetic processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The purpose, other functions, features, and advantages of the present disclosure are clarified by the following detailed description with reference to the accompanying drawings. The drawings are as described below. Fig. Figure 1 shows a block diagram illustrating an example of a configuration of a brushless motor system according to a first embodiment. Fig. Figure 2 shows a representation that schematically illustrates a relationship between a d-axis and a q-axis of a brushless motor according to an exemplary embodiment. Fig. Figure 3 shows a graph illustrating an example where a phase lead angle mapping according to the embodiment and a phase lead angle mapping value are set. Fig. Figure 4A shows a graph illustrating an example of a relationship between rotational speed and torque of the brushless motor and a relationship between a d-axis current and torque when a motor application voltage Va is equal to Vs. Fig. Figure 4B shows a graph illustrating an example of a relationship between the rotational speed and the torque of the brushless motor and a relationship between the d-axis current and the torque when the motor application voltage Va is equal to Vs / 2. Fig. Figure 5 shows a block diagram illustrating a configuration of a motor control device according to a comparative example. Fig. Figure 6 shows a flowchart illustrating an example of a phase advance angle control processing sequence by the motor control device according to the first embodiment. Fig. Figure 7A shows a graph illustrating another example where the phase advance angle mapping of the brushless motor is set when the motor application voltage Va is equal to Vs. Fig. Figure 7B shows a graph illustrating another example of the relationship between the rotational speed and the torque of the brushless motor when the motor application voltage Va is equal to Vs. Fig. Figure 8 shows a diagram that schematically illustrates an example of an upper reversal position and a lower reversal position of a wiper arm provided on a windshield. Fig. Figure 9 shows a graph illustrating the result of a simulation of a rotational speed, phase advance angle, q-axis current and d-axis current of a windscreen wiper motor at the upper reversing position and the lower reversing position of the windscreen wiper arm. Fig. Figure 10 shows a flowchart illustrating an example of a phase advance angle control processing sequence by a motor control device according to a second embodiment. Fig. Figure 11A shows a representation that is an example of a correction value table in which a load and a phase lead angle correction value are linked. Fig. Figure 11B shows a representation illustrating an example of a phase lead angle mapping in which a phase lead angle mapping value and a rotational speed are linked. Fig. Figure 11C shows a diagram illustrating an example of a correspondence relationship between a direction of rotation and a load. Fig. Figure 12 shows a flowchart illustrating an example of a phase advance angle control processing sequence by a motor control device according to a third embodiment. Fig. Figure 13 shows a flowchart illustrating an example of a phase advance angle control processing sequence by a motor control device according to a fourth embodiment. DESCRIPTION OF EXAMPLES OF EXECUTION

[0012] Examples of modes for implementing the technology according to the present disclosure are described in detail below with reference to the drawings. [First embodiment]

[0013] Fig. Figure 1 shows a block diagram illustrating an example of the configuration of a brushless motor system 100 according to a first embodiment.

[0014] As it is in Fig. As illustrated in Figure 1, the brushless motor system 100 according to the present embodiment comprises a motor control device 10, an inverter 20, a brushless motor 30, and a temperature sensor 40. As an example, the brushless motor system 100 according to the present embodiment is used to drive a windshield wiper system that wipes the windshield or the like of a vehicle, but it is applicable to various types of auxiliary equipment attached to a vehicle. It should be noted that the brushless motor 30 is an example of a motor.

[0015] The motor control device 10 is a control unit connected to the inverter 20 and controls the operation of the brushless motor 30 by the inverter 20. The motor control device 10 includes a microcomputer or the like. The microcomputer includes, for example, a CPU (central processing unit), a ROM (read-only memory), a RAM (random access memory), and the like.

[0016] The inverter 20 has a switching element (not shown) arranged between the motor control device 10 and the brushless motor 30. The switching element connects and disconnects an external power supply (not shown) and an armature coil (not shown) of the brushless motor 30. The switching element comprises, for example, a semiconductor element such as a FET (field-effect transistor). Furthermore, the switching element has, in particular, three switching elements on the positive electrode side, corresponding to the U-phase, the V-phase, and the W-phase, which are connected to the positive electrodes of the external power supply, and three switching elements on the negative electrode side, corresponding to the U-phase, the V-phase, and the W-phase, which are connected to the negative electrode side of the external power supply.When the switching element under the control of the motor control device 10 is connected (switched on), each of the armature coils receives current from the external power supply. When the switching element under the control of the motor control device 10 is disconnected (switched off), each of the armature coils receives no current from the external power supply. It should be noted that the external power supply is a battery, a capacitor, or the like, mounted on the vehicle.

[0017] As an example, a three-phase two-pole or a three-phase four-pole motor is used as a brushless motor 30. The brushless motor 30 has a stator (not shown) and a rotor (not shown). Additionally, the brushless motor 30 has, for example, a cylindrical housing (not shown) with a bottom. The brushless motor 30 is provided with the stator, which is fixed to the inner circumference of the housing. The stator has armature coils for three phases. In particular, the stator has armature coils for the U-phase, the V-phase, and the W-phase. The rotor is located inside the stator. The rotor has a rotating shaft (not shown) and a permanent magnet (not shown) attached to the rotating shaft. A plurality of bearings (not shown) are provided. The rotating shaft is supported by the plurality of bearings in such a way that it is rotatable.

[0018] The temperature sensor 40 is a sensor that measures the temperature of the brushless motor 30. A non-contact or contact sensor is used. Temperature information resulting from the measurement by the temperature sensor 40 is output to the motor control device 10.

[0019] The motor control device 10 according to the present embodiment comprises a position detection unit 11, a speed control unit 12, a phase advance angle setting unit 13, a memory 14, a phase advance angle correction unit 15, a three-phase conversion unit 16 and a PWM (pulse width modulation) drive control unit 17.

[0020] The position sensing unit 11 receives rotary position signals (for example, every 60° in electrical angle) from the brushless motor 30 via three (not shown) Hall-effect ICs attached to the brushless motor 30. The position sensing unit 11 interpolates and estimates a position between the rotary position signals based on these signals, thereby calculating an electrical angle θ. The position sensing unit 11 outputs the calculated electrical angle θ to the three-phase conversion unit 16. Additionally, the position sensing unit 11 receives the current speed (the actual rotational speed, also referred to below as the "actual rotational speed") based on the conversion using the rotary position signals.The position detection unit 11 outputs the converted actual rotational speed ω to both the speed control unit 12 and the phase advance angle setting unit 13.

[0021] The speed control unit 12 receives a speed command with a target rotational speed, for example, from a higher-level device such as a PLC (Programmable Logic Controller). Additionally, if the motor control device 10 has a function for generating a program, the motor control device 10 itself can function as a PLC. The speed control unit 12 also receives the actual rotational speed ω from the position sensing unit 11, calculates a motor application voltage Va to reduce the difference between the target rotational speed contained in the speed command and the actual rotational speed ω, and outputs the calculated motor application voltage Va to both the phase advance angle setting unit 13 and the three-phase conversion unit 16. The motor application voltage Va is a voltage to be applied to the brushless motor 30.

[0022] Memory 14 stores a motor control program and necessary data. The motor control program is used to execute phase advance angle control processing according to the present embodiment. Additionally, memory 14 prestores a phase advance angle mapping. The phase advance angle mapping combines the phase advance angle mapping value and the load factor of the brushless motor 30. Memory 14 is an example of a memory unit.

[0023] The phase advance angle setting unit 13 calculates the load factor of the brushless motor 30 at the motor application voltage Va, which is a voltage to be applied to the brushless motor 30. Additionally, the phase advance angle setting unit 13 derives a phase advance angle mapping value from the phase advance angle mapping in the memory 14 using the calculated load factor and generates a phase advance angle θ calculated on the basis of the derived phase advance angle mapping value and the motor application voltage Va. adv The phase advance angle setting unit 13 displays the set phase advance angle θ. adv to the three-phase conversion unit 16. The phase advance angle setting unit 13 is an example of a calculation unit and a setting unit.

[0024] The phase lead angle correction unit 15 corrects the phase lead angle θ.adv depending on the temperature of the brushless motor 30. The temperature of the brushless motor 30 is obtained from the temperature sensor 40. In particular, it is conceivable to perform a correction using, for example, a data table in which a relationship between the temperature of the brushless motor 30 and the phase advance angle θ is defined. adv It is linked in advance. The phase advance angle correction unit 15 is an example of a correction unit.

[0025] Additionally, the phase lead angle correction unit 15 can adjust the phase lead angle θ advCorrection can be performed based on information received from an external source. It should be noted that the information received from an external source could be obtained, for example, via a LIN (Local Interconnect Network) as a LIN signal. In particular, it is conceivable to perform a correction using, for example, a data table containing the relationship between the LIN signal and the phase advance angle θ. adv is linked in advance.

[0026] The three-phase conversion unit 16 receives the electrical angle θ from the position detection unit 11, receives the motor application voltage Va from the speed control unit 12 and receives the phase advance angle θ advfrom the phase advance angle setting unit 13. The three-phase conversion unit 16 converts the motor application voltage Va into three-phase motor application voltages Vu, Vv and Vw based on the electrical angle θ and the phase advance angle θ. adv um. The three-phase conversion unit 16 outputs the converted three-phase motor supply voltages Vu, Vv and Vw to the PWM drive control unit 17.

[0027] The PWM drive control unit 17 receives the three-phase motor supply voltages Vu, Vv, and Vw from the three-phase conversion unit 16, generates PWM signals from these voltages, and outputs them to the inverter 20. The PWM drive control unit 17 is an example of a drive control unit.

[0028] Below are a d-axis and a q-axis specifically with reference to Fig. 2 described.

[0029] Fig. Figure 2 shows a diagram that schematically illustrates the relationship between the d-axis and the q-axis of the brushless motor 30 according to the present embodiment.

[0030] As it is in Fig. As illustrated in Figure 2, a d-phase coil and a q-phase coil are virtually configured in the brushless motor 30. The d-phase coil and the q-phase coil each rotate in sync with the rotation of the permanent magnet. The d-axis is the direction parallel to a magnetic flux of the magnet, and the q-axis is the direction perpendicular to the d-axis. A d-axis current is a current component that generates a magnetic flux parallel to a magnetic flux of the magnet. The d-axis current is a current component that does not contribute to the magnetic torque. A q-axis magnetic flux is a current component that generates a magnetic flux perpendicular to a magnetic flux of the magnet. The d-axis magnetic flux is a current component that generates the magnetic torque.

[0031] A negative d-axis current cancels out the magnet's magnetic flux and therefore weakens the field. This increases the current within a low-load range but allows for an increase in rotational speed.

[0032] Fig. Figure 3 shows a graph illustrating an example where a phase lead angle mapping according to the present embodiment and a phase lead angle mapping value are set. Fig. Figure 3 illustrates a load factor [%] on the horizontal axis and a phase advance angle mapping value [degrees] on the vertical axis. Note that the numerical values ​​in the graph are examples.

[0033] In a Fig. In the phase advance angle mapping M1 shown in Figure 3, the phase advance angle mapping value and the load factor of the brushless motor 30 are pre-linked, as described above. The phase advance angle mapping M1 is stored in memory 14. A load factor L is calculated, for example, using the following equation (1). L=Vb / Va

[0034] Here, Va represents a motor supply voltage, and the motor supply voltage Va is a voltage determined by the speed control unit 12. Vb represents a motor load voltage, and the motor load voltage Vb has a value obtained by subtracting the back EMF from the motor supply voltage Va. The motor load voltage Vb is calculated, for example, using the following equation (2). Vb=Va−k×ω

[0035] Here, k represents a counter-electromotive force constant and ω represents an actual rotational speed.

[0036] In Fig. 3 The phase advance angle mapping M1 is set such that a d-axis current Id of the brushless motor 30 is zero, for example, in a case where the motor application voltage Va equals Vs. The relationship between the phase advance angle θ is thus... adv and the phase lead angle mapping value θ mp expressed by the following equation (3). θadv=θmp×Va / Vs

[0037] Here, Va represents a motor application voltage and Vs represents a reference voltage (e.g. 13.5 V).

[0038] As an example, a case is described where the motor supply voltage Va is equal to Vs / 2. The load factor L of the brushless motor 30 in the case of Va = Vs / 2 is calculated using equations (1) and (2) described above. Next, the phase advance angle mapping value θ is determined. mp derived with reference to the phase lead angle mapping M1 using the calculated load factor L. The derived phase lead angle mapping value θ mp and the motor application voltage Va = Vs / 2 are inserted into the equation (3) described above to determine the phase advance angle θ adv to be calculated according to the motor application voltage Va.

[0039] The phase lead angle mapping M1 is set such that the phase lead angle is a phase lag angle, i.e., a negative angle, within a range where the load factor is smaller than a predetermined value. In particular, it is desirable that the range where the load factor is smaller than the predetermined value is a range where the load factor is negative. The "phase lead angle" according to the present embodiment has a positive phase lead angle and ALSO a phase lag angle, which is a negative phase lead angle.

[0040] Fig. Figure 4A shows a graph illustrating an example of the relationship between the rotational speed and the torque of the brushless motor 30 and the relationship between the d-axis current Id and the torque when the motor application voltage Va is equal to Vs. Fig. Figure 4B shows a graph illustrating an example of the relationship between the rotational speed and the torque of the brushless motor 30 and the relationship between the d-axis current Id and the torque when the motor application voltage Va is equal to Vs / 2.

[0041] In Fig. 4A and Fig. In the upper graph, the horizontal axis represents a torque [N·m], and the vertical axis represents the rotational speed [rpm]. A characteristic curve R1, illustrated in the upper graph, indicates a phase lead angle of 20°. A characteristic curve R2 indicates a phase lead angle of 10°. A characteristic curve R3 indicates a phase lead angle of 0°. A characteristic curve R4 indicates a case where, according to the present embodiment, Id is zero. Additionally, the horizontal axis of the lower graph represents a torque [N·m], and the vertical axis represents the d-axis current Id [A]. A characteristic curve I1, illustrated in the lower graph, indicates a phase lead angle of 20°. A characteristic curve I2 indicates a phase lead angle of 10°. A characteristic curve I3 indicates a phase lead angle of 0°. A characteristic curve I4 indicates a case in which, according to the present embodiment, Id is equal to zero.

[0042] As it is in Fig. 4A and Fig. As illustrated in Figure 4B, the phase advance angle is adjusted depending on the motor's applied voltage, which results in the d-axis current Id being essentially zero despite changes in the motor's applied voltage, rotational speed, and torque. This means that it is possible to implement control similar to an Id=0 control, which is a type of vector control.

[0043] It should be noted that a sinusoidal feed, or an essentially sinusoidal feed achieved using a waveform obtained by superimposing a third harmonic onto a sine wave, has been described above; however, its application is also possible with various feed methods, such as a square wave feed and a trapezoidal wave feed. In this case, it is not possible to achieve Id = 0 as with the sinusoidal feed, but it is possible to adjust the phase advance angle to minimize Id.

[0044] Fig. Figure 5 shows a block diagram illustrating the configuration of a motor control device 200 according to a comparative example.

[0045] As it is in Fig. As illustrated in Figure 5, the motor control device 200 according to the comparative example comprises a speed control unit 201, a position sensing unit 202, a current control unit 203, an inversion coordinate conversion unit 204, a three-phase conversion unit 205, a PWM drive control unit 206, a current sensing unit 207, a two-phase conversion unit 208 and a coordinate conversion unit 209.

[0046] The motor control device 200, as described in the comparative example, is configured to perform vector control. The motor control device 200, which performs vector control, requires the current sensing unit 207, which senses the current, and the inversion coordinate conversion unit 204 and the coordinate conversion unit 209, which are arithmetic units that each perform an arithmetic operation of converting coordinates, as described above. In particular, in a case where the current exhibits large fluctuations, the periodicity of the current control must be shortened. It is necessary to employ a microcomputer with high processing power. Therefore, in a case where cost is a concern, the phase advance angle is fixed, or in some cases, the phase advance angle is preset depending on the rotational speed.In this case, in applications where the rotational speed and load fluctuate, the d-axis current can increase excessively, and efficiency and speed controllability can decrease.

[0047] In contrast, the motor control device 10 according to the present embodiment stores and has the phase advance angle mapping M1, in which the phase advance angle mapping value and the load factor of the brushless motor 30 are linked. The motor control device 10 calculates the load factor L of the brushless motor 30 at the motor application voltage Va and sets the phase advance angle θ. adv one that is based on the phase lead angle mapping value θ mp, which is obtained from the phase advance angle mapping M1 using the calculated load factor L, and the motor application voltage Va is calculated, and controls the brushless motor 30 with the set phase advance angle θ adv .

[0048] This allows the d-axis current to be controlled despite changes in the load and rotational speed of the brushless motor 30, without the need to detect a current and perform complicated arithmetic processing.

[0049] Additionally, in a case where the rotational speed of the brushless motor 30 is equal to or less than a threshold value, the phase advance angle setting unit 13 can switch to a mode in which the phase advance angle θ advis fixed. It should be noted that a suitable value is set as the threshold, for example, based on existing knowledge or a research result. For example, in a case where the electrical angle is measured using a Hall-effect IC, an estimation error in the electrical angle increases more sharply at a low starting speed. The fixation on the phase advance angle θ adv , which enables a torque to be reliably generated, is therefore desirable.

[0050] Additionally, the phase lead angle correction unit 15 can adjust the phase lead angle θ adv The parameters are corrected depending on the temperature of the brushless motor 30. This makes it possible to reduce the influence of properties that change due to the altered temperature and heat generated by the motor.

[0051] Additionally, the phase lead angle correction unit 15 can adjust the phase lead angle θ adv based on information (for example, a LIN signal) received from an external source, the phase advance angle θ can be corrected. adv to correct depending on changes in ambient temperature and the external environment.

[0052] The following are the effects of the motor control device 10 according to the first embodiment with reference to Fig. 6 described.

[0053] Fig. Figure 6 shows a flowchart illustrating an example of the process of phase advance angle control processing by the motor control device 10 according to the first embodiment.

[0054] First, when the motor control device 10 is instructed to perform a phase advance angle control processing, a motor control program is started to execute the subsequent steps.

[0055] In step S101 and Fig. The position sensing unit 11 receives rotary position signals, for example, at electrical angles of 60° of the brushless motor 30, from three (not shown) Hall ICs attached to the brushless motor 30. The position sensing unit 11 interpolates and estimates a position between the rotary position signals based on the signals, thereby calculating the electrical angle θ. The position sensing unit 11 outputs the calculated electrical angle θ to the three-phase conversion unit 16. Additionally, the position sensing unit 11 receives the actual rotational speed ω based on a conversion using the rotary position signals. The position sensing unit 11 outputs the converted actual rotational speed ω to both the speed control unit 12 and the phase advance angle setting unit 13.

[0056] In step S102, the speed control unit 12 receives, for example, a speed command with a target rotational speed from a higher-level device such as a PLC and receives the actual rotational speed ω from the position sensing unit 11. The speed control unit 12 calculates the motor application voltage Va to reduce the difference between the target rotational speed contained in the speed command and the actual rotational speed ω and outputs the calculated motor application voltage Va to both the phase advance angle setting unit 13 and the three-phase conversion unit 16.

[0057] In step S103, the phase advance angle setting unit 13 estimates the load of the brushless motor 30. For example, (motor application voltage Va - back electromotive force) is estimated as a parameter corresponding to the load. In particular, as an example, the motor load voltage Vb is calculated using equation (2) described above. In step S104, the phase advance angle setting unit 13 calculates the load factor L from the motor application voltage Va calculated in step S102 and the motor load voltage Vb calculated in step S103, using equation (1) described above as an example. In step S105, the phase advance angle setting unit 13 derives the phase advance angle mapping value θ. mp with reference to the phase lead angle mapping M1 stored in memory 14, using the load factor L calculated in step S104.

[0058] In step S106, the phase lead angle setting unit 13 sets the phase lead angle mapping value θ derived in step S105. mp and insert the motor application voltage Va calculated in step S102 into equation (3) described above to determine the phase advance angle θ adv to calculate the phase advance angle corresponding to the motor supply voltage Va. The phase advance angle setting unit 13 outputs the set phase advance angle θ. adv to the three-phase conversion unit 16.

[0059] In step S107, the three-phase conversion unit 16 receives the electrical angle θ from the position detection unit 11, receives the motor application voltage Va from the speed control unit 12, and receives the phase advance angle θ. advfrom the phase advance angle setting unit 13. The three-phase conversion unit 16 converts the motor application voltage Va on the basis of the electrical angle θ and the phase advance angle θ. adv The three-phase conversion unit 16 converts the three-phase motor voltages Vu, Vv, and Vw into the three-phase motor voltages Vu, Vv, and Vw. The PWM drive control unit 17 outputs these converted three-phase motor voltages Vu, Vv, and Vw to the PWM drive control unit 17. The PWM drive control unit 17 controls the drive of the brushless motor 30 based on the motor voltages Vu, Vv, and Vw, thus completing the phase advance angle control processing by this motor control program.

[0060] Fig. Figure 7A shows a graph illustrating another example where the phase advance angle mapping of the brushless motor 30 is set when the motor application voltage Va equals Vs. It also shows Fig. 7B a graph illustrating another example of the relationship between the rotational speed and the torque of the brushless motor 30 when the motor application voltage Va is equal to Vs.

[0061] One in Fig. 7A The illustrated phase advance angle diagram M3 is set such that the phase advance angle of the brushless motor 30 is larger within a specific load factor range.

[0062] This is the in Fig. 7A illustrates phase lead angle mapping M3 set such that the phase lead angle mapping value θ mp In comparison to the phase advance angle mapping M1, which is set such that the d-axis current Id is zero, except that it is larger within the specific load factor range, a field weakening is induced by the negative d-axis current Id in order to increase the rotational speed of the motor.

[0063] This means that, as can be seen from a Fig. Figure 7B illustrates the characteristic curve R5, which indicates a field weakening region that is set depending on the operating range of a product, making it possible to increase the rotational speed of the motor within the operating range of the product and to compensate for the characteristics within the operating range.

[0064] Below is a result of a simulation in which the phase advance angle control processing by the motor control device 10 according to the present embodiment is applied to a windshield wiper system, with reference to Fig. 8 and Fig. 9 described.

[0065] Fig. Figure 8 shows a diagram schematically illustrating an example of an upper reversal position P1 and a lower reversal position P2 of wiper arms 51 and 52, which are intended for a windshield 50. Additionally, it shows Fig. 9 a graph illustrating a result of a simulation of the rotational speed, phase advance angle, q-axis current Iq and d-axis current Id of a windscreen wiper motor at the upper reversing position P1 and the lower reversing position P2 of the windscreen wiper arms 51 and 52.

[0066] A load change caused by wind resistance is simulated using the methods described above. Fig. The phase lead angle mapping M1 illustrated in 3 is reproduced, and the effects of the phase lead angle control processing according to the present embodiment are confirmed.

[0067] A case is assumed in which the brushless motor 30 according to the present embodiment is driven in a direct or indirect connection and is used to drive the wiper arms 51 and 52 of the wiper system, as described in Fig. Figure 8 illustrates this. The wiper arms 41 and 42 are designed for the windshield 50 and move back and forth between the upper reversal position P1 and the lower reversal position P2.

[0068] To reliably generate torque, the phase advance angle is fixed at 0° when the motor's rotational speed is low. The q-axis current Iq has a value proportional to the torque generated by the motor. The load therefore differs significantly between parking and high-speed driving, as is the case in... Fig. Figure 9 illustrates this. In contrast, the phase advance angle changes appropriately depending on the load condition. It is shown that the d-axis current Id can be kept essentially at zero regardless of the load condition.

[0069] A forward stroke, i.e., a stroke from the lower reversing position P2 to the upper reversing position P1, changes the phase lead angle to a phase lag angle (i.e., a negative phase lead angle) because the influence of wind causes regenerative operation. Conversely, a return stroke, i.e., a stroke from the upper reversing position P1 to the lower reversing position P2, increases the phase lead angle because the influence of wind increases the load.

[0070] In this way, the present embodiment allows the control of the d-axis current despite changes in the load and the rotational speed of the motor, without the need to detect a current and perform complicated arithmetic processing. [Second embodiment]

[0071] In the first embodiment, a mode was described in which the phase lead angle control processing is performed using the phase lead angle mapping, where the phase lead angle mapping value and the load factor are linked. According to a second embodiment, a mode is described in which the phase lead angle control processing is performed using a phase lead angle mapping, where the phase lead angle mapping value and the rotational speed are linked.

[0072] The functional configuration of a motor control device 10A according to the second embodiment is similar to that of the motor control device 10 (see Fig. 1) according to the first embodiment. The memory 14 of the motor control device 10A according to the second embodiment stores a phase advance angle mapping in which the phase advance angle mapping value and the rotational speed of the brushless motor 30 are pre-linked. The memory 14 is an example of the memory unit.

[0073] The phase lead angle setting unit 13 is an example of an estimation unit and estimates the load of the brushless motor 30. The phase lead angle setting unit 13 is an example of a calculation unit and calculates a phase lead angle correction value based on the estimated load. The phase lead angle setting unit 13 is an example of a setting unit and sets a phase lead angle calculated based on the phase lead angle mapping value obtained from the phase lead angle mapping in memory 14, using the actual rotational speed of the brushless motor 30 and the calculated phase lead angle correction value.

[0074] The PWM drive control unit 17 is an example of a drive control unit and controls the brushless motor 30 at the phase advance angle set by the phase advance angle setting unit 13.

[0075] The following are the effects of the motor control device 10A according to the second embodiment with reference to Fig. 10 described.

[0076] Fig. Figure 10 shows a flowchart illustrating an example of the process of phase advance angle control processing by the motor control device 10A according to the second embodiment.

[0077] First, when the motor control device 10A is instructed to perform phase advance angle control processing, a motor control program is started to execute each of the following steps.

[0078] Step S111 of Fig. The position sensing unit 11 receives rotary position signals (for example, every 60° in electrical angle) from the brushless motor 30 via three (not illustrated) Hall-effect ICs attached to the brushless motor 30. The position sensing unit 11 interpolates and estimates a position between the rotary position signals based on the signals, thereby calculating an electrical angle. The position sensing unit 11 outputs the calculated electrical angle to the three-phase conversion unit 16. Additionally, the position sensing unit 11 receives the actual rotational speed based on a conversion using the rotary position signals. The position sensing unit 11 outputs the converted actual rotational speed to both the speed control unit 12 and the phase advance angle setting unit 13.

[0079] The speed control unit 12 then receives, for example, a speed command with a target rotational speed from a higher-level device such as a PLC and receives the actual rotational speed from the position sensing unit 11. The speed control unit 12 calculates a motor application voltage to reduce the difference between the target rotational speed contained in the speed command and the actual rotational speed and outputs the calculated motor application voltage to both the phase advance angle setting unit 13 and the three-phase conversion unit 16.

[0080] In step S112, the phase advance angle setting unit 13 estimates the load of the brushless motor 30. For example, (motor application voltage - back electromotive force) is estimated as a parameter corresponding to the load. In particular, as an example, the motor load voltage is calculated using equation (2) described above.

[0081] In step S113, the phase lead angle setting unit 13 calculates a phase lead angle correction value based on the load estimated in step S112 (for example, the motor load voltage).

[0082] Fig. Figure 11A shows a diagram illustrating an example of a correction value table in which the load and the phase lead angle correction value are linked. This correction value table is pre-stored in memory 14. As an example, the phase lead angle setting unit 13 calculates a phase lead angle correction value with reference to the Fig. 11A illustrated correction value table using the estimated load (for example, the motor load voltage).

[0083] In step S114, the phase lead angle setting unit 13 derives a phase lead angle mapping value using the phase lead angle mapping stored in memory 14 and the actual rotational speed calculated in step S111.

[0084] Fig. Figure 11B shows a diagram illustrating an example of the phase lead angle mapping, in which the phase lead angle mapping value and the rotational speed are linked. This phase lead angle mapping is pre-stored in memory 14. As an example, the phase lead angle setting unit 13 calculates a phase lead angle mapping value with reference to the value in Fig. Figure 11B illustrated phase lead angle mapping using the actual rotational speed.

[0085] In step S115, the phase lead angle setting unit 13 sets a phase lead angle calculated based on the phase lead angle mapping value derived in step S114 and the phase lead angle correction value calculated in step S113. The phase lead angle setting unit 13 outputs the set phase lead angle to the three-phase conversion unit 16.

[0086] Fig. Figure 11C shows a diagram illustrating an example of the correspondence relationship between the direction of rotation and the load. As an example, the phase lead angle setting unit 13 calculates a phase lead angle by multiplying the phase lead angle mapping value by the phase lead angle correction value. The sign (+ / -) of the phase lead angle is determined based on the Fig. 11C illustrated the correspondence relationship.

[0087] In step S116, the three-phase conversion unit 16 receives an electrical angle from the position sensing unit 11, a motor supply voltage from the speed control unit 12, and a phase lead angle from the phase lead angle setting unit 13. The three-phase conversion unit 16 converts the motor supply voltage into three-phase (U-phase, V-phase, and W-phase) motor supply voltages based on the electrical angle and the phase lead angle. The three-phase conversion unit 16 outputs the converted three-phase motor supply voltages to the PWM drive control unit 17. The PWM drive control unit 17 controls the drive of the brushless motor 30 on the basis of the three-phase motor application voltages and brings the phase advance angle control processing to a conclusion through this motor control program.

[0088] In this way, the present embodiment, as in the embodiment described above, allows the d-axis current to be controlled despite changes in the load and rotational speed of the motor, without the need to detect a current and perform complicated arithmetic processing. [Third embodiment]

[0089] According to a third embodiment, a mode is described in which the phase lead angle control processing is performed using a phase lead angle mapping in which the phase lead angle mapping value and the load are linked.

[0090] The functional configuration of a motor control device 10B according to the third embodiment is similar to that of the motor control device 10 (see Fig. 1) according to the first embodiment. The memory 14 of the motor control device 10B according to the third embodiment stores a phase advance angle mapping in which the phase advance angle mapping value and the load of the brushless motor 30 are pre-linked. The memory 14 is an example of the memory unit.

[0091] The phase lead angle setting unit 13 is an example of the estimation unit and estimates the load of the brushless motor 30. The phase lead angle setting unit 13 is an example of the calculation unit and calculates a phase lead angle correction value based on the actual rotational speed. The phase lead angle setting unit 13 is an example of the setting unit and sets a phase lead angle calculated based on the phase lead angle mapping value obtained from the phase lead angle mapping in memory 14 using the load of the brushless motor 30 and the calculated phase lead angle correction value.

[0092] The PWM drive control unit 17 is an example of the drive control unit and controls the brushless motor 30 with the phase advance angle set by the phase advance angle setting unit 13.

[0093] The following are the effects of the motor control device 10B according to the third embodiment with reference to Fig. 12 described.

[0094] Fig. Figure 12 shows a flowchart illustrating an example of the process of phase advance angle control processing by the motor control device 10B according to the third embodiment.

[0095] First, when the motor control device 10B is instructed to perform phase advance angle control processing, a motor control program is started to execute each of the following steps.

[0096] In step S121 of Fig. The position sensing unit 11 receives rotary position signals (for example, every 60° in electrical angle) from the brushless motor 30 via three Hall-effect ICs (not shown) attached to the brushless motor 30. The position sensing unit 11 interpolates and estimates a position between the rotary position signals based on the signals, thereby calculating an electrical angle. The position sensing unit 11 outputs the calculated electrical angle to the three-phase conversion unit 16. Additionally, the position sensing unit 11 receives the actual rotational speed based on a conversion using the rotary position signals. The position sensing unit 11 outputs the converted actual rotational speed to both the speed control unit 12 and the phase advance angle setting unit 13.

[0097] The speed control unit 12 then receives, for example, a speed command specifying a target rotational speed from a higher-level device such as a PLC and obtains the actual rotational speed from the position sensing unit 11. The speed control unit 12 calculates a motor application voltage to reduce the difference between the target rotational speed contained in the speed command and the actual rotational speed and outputs the calculated motor application voltage to both the phase advance angle setting unit 13 and the three-phase conversion unit 16.

[0098] In step S122, the phase advance angle setting unit 13 estimates the load of the brushless motor 30. For example, (motor application voltage - back electromotive force) is estimated as a parameter corresponding to the load. In particular, as an example, the motor load voltage is calculated using equation (2) described above.

[0099] In step S123, the phase advance angle setting unit 13 calculates a phase advance angle correction value based on the actual rotational speed calculated in step S121. In this case, the Fig. Figure 11A illustrates the correction value table described above, which can be used as a correction value table in which the rotational speed and the phase lead angle correction value are linked. This correction value table is pre-stored in memory 14. As an example, the phase lead angle setting unit 13 calculates a phase lead angle correction value with reference to the correction value table using the calculated actual rotational speed.

[0100] In step S124, the phase lead angle setting unit 13 derives a phase lead angle mapping value with reference to the phase lead angle mapping stored in memory 14, using the load estimated in step S122. In this case, the Fig. Figure 11B illustrates the phase lead angle mapping described above, which can be used as a phase lead angle mapping in which the load and the phase lead angle mapping value are linked. This phase lead angle mapping is pre-stored in memory 14. As an example, the phase lead angle setting unit 13 calculates a phase lead angle mapping value with reference to the phase lead angle mapping using the estimated load.

[0101] In step S125, the phase lead angle setting unit 13 sets a phase lead angle calculated based on the phase lead angle mapping value derived in step S124 and the phase lead angle correction value calculated in step S123. As an example, the phase lead angle setting unit 13 calculates a phase lead angle by multiplying the phase lead angle mapping value by the phase lead angle correction value. The phase lead angle setting unit 13 outputs the set phase lead angle to the three-phase conversion unit 16.

[0102] In step S126, the three-phase conversion unit 16 receives an electrical angle from the position sensing unit 11, a motor supply voltage from the speed control unit 12, and a phase lead angle from the phase lead angle setting unit 13. The three-phase conversion unit 16 converts the motor supply voltage into three-phase (U-phase, V-phase, and W-phase) motor supply voltages based on the electrical angle and the phase lead angle. The three-phase conversion unit 16 outputs the converted three-phase motor supply voltages to the PWM drive control unit 17. The PWM drive control unit 17 controls the drive of the brushless motor 30 on the basis of the three-phase motor application voltages and brings the phase advance angle control processing to a conclusion through this motor control program.

[0103] In this way, the present embodiment, as in the first embodiment described above, allows the d-axis current to be controlled despite changes in the load and rotational speed of the motor, without the need to detect a current and perform complicated arithmetic processing. [Fourth example]

[0104] According to a fourth embodiment, a mode is described in which the phase lead angle control processing is performed using a first phase lead angle mapping in which the phase lead angle mapping value and the rotational speed are linked, and a second phase lead angle mapping in which the phase lead angle mapping value and the load are linked.

[0105] The functional configuration of a motor control device 10C according to the fourth embodiment is similar to that of the motor control device 10 (see Fig. 1) according to the first embodiment. The memory 14 of the motor control device 10C according to the fourth embodiment stores a first phase lead angle mapping, in which the phase lead angle mapping value and the rotational speed of the brushless motor 30 are linked, and a second phase lead angle mapping, in which the phase lead angle mapping value and the load are linked. The memory 14 is an example of a first memory unit and a second memory unit. The phase lead angle setting unit 13 is an example of an estimation unit and estimates the load of the brushless motor 30.

[0106] The phase lead angle setting unit 13 is an example of the setting unit and sets a phase lead angle calculated using a first phase lead angle mapping value obtained from the first phase lead angle mapping in the memory 14 using the actual rotational speed of the brushless motor 30, and a second phase lead angle mapping value obtained from the second phase lead angle mapping in the memory 14 using the estimated load.

[0107] The PWM drive control unit 17 is an example of the drive control unit and controls the brushless motor 30 at the phase advance angle set by the phase advance angle setting unit 13.

[0108] The following are the effects of the motor control device 10C according to the fourth embodiment, with reference to Fig. 13 described.

[0109] Fig. Figure 13 shows a flowchart illustrating an example of the process of phase advance angle control processing by the motor control device 10C according to the fourth embodiment.

[0110] First, when the motor control device 10C is instructed to perform phase advance angle control processing, a motor control program is started to execute each of the following steps.

[0111] In step S131 of Fig. The position sensing unit 11 receives rotary position signals (for example, every 60° in electrical angle) from the brushless motor 30 via three Hall-effect ICs (not shown) attached to the brushless motor 30. The position sensing unit 11 interpolates and estimates a position between the rotary position signals based on the signals, thereby calculating an electrical angle. The position sensing unit 11 outputs the calculated electrical angle to the three-phase conversion unit 16. Additionally, the position sensing unit 11 receives the actual rotational speed based on a conversion using the rotary position signals. The position sensing unit 11 outputs the converted actual rotational speed to both the speed control unit 12 and the phase advance angle setting unit 13.

[0112] The speed control unit 12 then receives, for example, a speed command with a target rotational speed from a higher-level device such as a PLC and receives the actual rotational speed from the position sensing unit 11. The speed control unit 12 calculates a motor application voltage to reduce the difference between the target rotational speed contained in the speed command and the actual rotational speed and outputs the calculated motor application voltage to both the phase advance angle setting unit 13 and the three-phase conversion unit 16.

[0113] In step S132, the phase advance angle setting unit 13 estimates the load of the brushless motor 30. For example, (motor application voltage - back electromotive force) is estimated as a parameter corresponding to the load. In particular, as an example, the motor load voltage is calculated using equation (2) described above.

[0114] In step S133, the phase lead angle setting unit 13 derives a first phase lead angle mapping value with reference to the first phase lead angle mapping stored in memory 14, using the actual rotational speed calculated in step S131. For example, in this case, the phase lead angle setting unit 13 calculates a first phase lead angle mapping value with reference to the first phase lead angle mapping stored in memory 14. Fig. Figure 11B illustrates what has been described above, using the actual rotational speed.

[0115] In step S134, the phase lead angle setting unit 13 derives a second phase lead angle mapping value with reference to the second phase lead angle mapping stored in memory 14, using the load estimated in step S132. In this case, the Fig. Figure 11B illustrated the first phase lead angle mapping described above, as the second phase lead angle mapping, in which the load and the phase lead angle mapping value are linked. As an example, the phase lead angle setting unit 13 calculates a second phase lead angle mapping value with reference to the second phase lead angle mapping using the estimated load.

[0116] In step S135, the phase lead angle setting unit 13 sets a phase lead angle calculated using the first phase lead angle mapping value derived in step S133 and the second phase lead angle mapping value derived in step S134. As an example, the phase lead angle setting unit 13 calculates a phase lead angle by multiplying the first phase lead angle mapping value by the second phase lead angle mapping value. The phase lead angle setting unit 13 outputs the set phase lead angle to the three-phase conversion unit 16.

[0117] In step S136, the three-phase conversion unit 16 receives an electrical angle from the position sensing unit 11, a motor supply voltage from the speed control unit 12, and a phase lead angle from the phase lead angle setting unit 13. The three-phase conversion unit 16 converts the motor supply voltage into three-phase (U-phase, V-phase, and W-phase) motor supply voltages based on the electrical angle and the phase lead angle. The three-phase conversion unit 16 outputs the converted three-phase motor supply voltages to the PWM drive control unit 17. The PWM drive control unit 17 controls the drive of the brushless motor 30 on the basis of the three-phase motor application voltages and brings the phase advance angle control processing to a conclusion through this motor control program.

[0118] In this way, the present embodiment, as in the first embodiment described above, allows the d-axis current to be controlled despite changes in the load and rotational speed of the motor, without the need to detect a current and perform complicated arithmetic processing.

[0119] With regard to the embodiments described above, the following additional information is disclosed below. (Supplementary Note 1)

[0120] Motor control device with: a storage unit configured to store a phase lead angle map in which a phase lead angle map value and a load factor of a motor are pre-linked, a calculation unit configured to calculate a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor, a setting unit configured to set a phase advance angle calculated on the basis of a phase advance angle mapping value and the motor application voltage, wherein the phase advance angle mapping value is obtained from the phase advance angle mapping using the calculated load factor, and a drive control unit that is configured to control the motor at the set phase advance angle. (Supplementary note 2)

[0121] Motor control device according to supplementary note 1, in which the phase advance angle mapping is set such that a d-axis current of the motor is zero. (Supplementary note 3)

[0122] Motor control device according to supplementary note 2, in which the phase advance angle mapping is set such that a phase advance angle within a specific load factor range is greater than a phase advance angle of the phase advance angle mapping which is set such that the d-axis current of the motor is zero. (Supplementary note 4)

[0123] Motor control device according to one of the supplementary notes 1 to 3, in which the phase lead angle mapping is set such that the phase lead angle mapping is a phase lag angle within a range in which the load factor is smaller than a predetermined value. (Supplementary note 5)

[0124] Motor control device according to supplementary note 4, in which the range in which the load factor is less than the predetermined value is a range in which the load factor is negative. (Supplementary note 6)

[0125] Motor control device according to one of the supplementary notes 1 to 5, in which the setting unit switches to a mode in which the phase advance angle is fixed in a case where the rotational speed of the motor is equal to or less than a threshold value. (Supplementary note 7)

[0126] Motor control device according to one of the supplementary notes 1 to 6, which includes a correction unit configured to correct a phase advance angle depending on the temperature of the motor. (Supplementary Note 8)

[0127] Motor control device according to one of the supplementary notes 1 to 7, which has a correction unit configured to correct the phase advance angle based on information obtained from outside. (Supplementary note 9)

[0128] Motor control device with: a storage unit configured to store a phase lead angle map in which a phase lead angle map value and a rotational speed of a motor are pre-linked, an estimating unit configured to estimate the load of the engine, a calculation unit that is configured to calculate a phase lead angle correction value based on the estimated load, a setting unit configured to set a phase lead angle calculated on the basis of a phase lead angle mapping value and the calculated phase lead angle correction value, wherein the phase lead angle mapping value is obtained from the phase lead angle mapping using an actual rotational speed of the motor, and a drive control unit that is configured to control the motor at the set phase advance angle. (Supplementary Note 10)

[0129] Motor control device with: a storage unit configured to store a phase lead angle map in which a phase lead angle map value and a motor load are pre-linked, an estimating unit configured to estimate the load of the engine, a calculation unit configured to calculate a phase advance angle correction value based on the actual rotational speed of the motor, a setting unit configured to set a phase lead angle calculated on the basis of a phase lead angle mapping value and the calculated phase lead angle correction value, the phase lead angle mapping value being obtained from the phase lead angle mapping using the estimated load of the motor, and a drive control unit that is configured to control the motor at the set phase advance angle. (Supplementary Note 11)

[0130] Motor control device with: a first storage unit configured to store a first phase lead angle map in which a phase lead angle map value and a rotational speed of a motor are pre-linked, a second storage unit configured to store a second phase lead angle map in which a phase lead angle map value and a load of the motor are pre-linked, an estimating unit configured to estimate the load of the engine, a setting unit configured to set a phase lead angle calculated using a first phase lead angle map value and a second phase lead angle map value, wherein the first phase lead angle map value is obtained from the first phase lead angle map using an actual rotational speed of the motor, and the second phase lead angle map value is obtained from the second phase lead angle map using the estimated load, and a drive control unit that is configured to control the motor at the set phase advance angle. (Supplementary Note 12)

[0131] Motor control method by a motor control device comprising a memory unit configured to store a phase lead angle map in which a phase lead angle map value and a load factor of a motor are pre-linked, wherein the motor control method, by the motor control device, comprises: Calculating a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor, Setting a phase lead angle, which is calculated based on a phase lead angle mapping value and the motor application voltage, wherein the phase lead angle mapping value is obtained from the phase lead angle mapping using the calculated load factor, and Controlling the motor at the set phase advance angle.

[0132] The present disclosure is described according to the embodiments shown; however, the disclosure is not limited to these embodiments and configurations. The present disclosure itself includes various modifications and examples within the equivalent scope. Additionally, various combinations and modes, including one, several, or fewer of the elements, also fall within the scope and concept of the present disclosure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2023-090344

[0001] JP 2007 - 049843 A

[0005]

Claims

[1] Motor control device (10) comprising: a storage unit (14) configured to store a phase lead angle map in which a phase lead angle map value and a load factor of a motor (30) are pre-linked, a calculation unit (13) configured to calculate a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor, a setting unit (13) configured to set a phase advance angle calculated on the basis of a phase advance angle mapping value and the motor application voltage, wherein the phase advance angle mapping value is obtained from the phase advance angle mapping using the calculated load factor, and a drive control unit (17) which is configured to control the motor at the set phase advance angle. [2] Motor control device according to claim 1, wherein the phase advance angle mapping is set such that a d-axis current of the motor is zero. [3] Motor control device according to claim 2, wherein the phase advance angle mapping is set such that a phase advance angle within a specific load factor range is greater than a phase advance angle of the phase advance angle mapping which is set such that the d-axis current of the motor is zero. [4] Motor control device according to claim 1, wherein the phase lead angle mapping is set such that the phase lead angle mapping is a phase lag angle within a range in which the load factor is smaller than a predetermined value. [5] Motor control device according to claim 4, wherein the range in which the load factor is less than the predetermined value is a range in which the load factor is negative. [6] Motor control device according to claim 1, wherein the setting unit switches to a mode in which the phase advance angle is fixed in a case where the rotational speed of the motor is equal to or less than a threshold value. [7] Motor control device according to claim 1, further comprising a correction unit (15) configured to correct a phase advance angle depending on the temperature of the motor. [8] Motor control device according to claim 1, further comprising a correction unit (15) configured to correct the phase advance angle based on information obtained from outside. [9] Motor control device (10A) with: a storage unit (14) configured to store a phase lead angle map in which a phase lead angle map value and a rotational speed of a motor are pre-linked, an estimation unit (13) configured to estimate a load of the engine, a calculation unit (13) that is configured to calculate a phase lead angle correction value based on the estimated load, a setting unit (13) configured to set a phase lead angle calculated on the basis of a phase lead angle mapping value and the calculated phase lead angle correction value, wherein the phase lead angle mapping value is obtained from the phase lead angle mapping using an actual rotational speed of the motor, and a drive control unit (17) which is configured to control the motor at the set phase advance angle. [10] Motor control device (10B) comprising: a storage unit (14) configured to store a phase lead angle map in which a phase lead angle map value and a load of a motor are pre-linked, an estimation unit (13) configured to estimate a load of the engine, a calculation unit (13) configured to calculate a phase advance angle correction value based on an actual rotational speed of the motor, a setting unit (13) configured to set a phase lead angle calculated on the basis of a phase lead angle mapping value and the calculated phase lead angle correction value, wherein the phase lead angle mapping value is obtained from the phase lead angle mapping using the estimated load of the motor, and a drive control unit (17) which is configured to control the motor at the set phase advance angle. [11] Motor control device (10C) comprising: a first storage unit (14) configured to store a first phase lead angle map in which a phase lead angle map value and a rotational speed of a motor are pre-linked, a second storage unit (14) configured to store a second phase lead angle map in which a phase lead angle map value and a load of the motor are pre-linked, an estimation unit (13) configured to estimate the load of the motor, a setting unit (13) configured to set a phase lead angle calculated using a first phase lead angle map value and a second phase lead angle map value, wherein the first phase lead angle map value is obtained from the first phase lead angle map using an actual rotational speed of the motor and the second phase lead angle map value is obtained from the second phase lead angle map using the estimated load, and a drive control unit (17) which is configured to control the motor at the set phase advance angle. [12] Motor control method performed by a motor control device (10) having a storage unit (14) configured to store a phase lead angle mapping in which a phase lead angle mapping value and a load factor of a motor (30) are pre-linked, wherein the motor control method, by the motor control device, comprises: Calculating a load factor of the motor at a motor application voltage, which is a voltage to be applied to the motor, Setting a phase lead angle, which is calculated based on a phase lead angle mapping value and the motor application voltage, wherein the phase lead angle mapping value is obtained from the phase lead angle mapping using the calculated load factor, and Controlling the motor at the set phase advance angle.

Images